Materials for semiconductor package mount applications and methods of using the same

Abstract

An embodiment composite material for semiconductor package mount applications may include a first component including a tin-silver-copper alloy and a second component including a tin-bismuth alloy or a tin-indium alloy. The composite material may form a reflowed bonding material having a room temperature tensile strength in a range from 80 MPa to 100 MPa when subjected to a reflow process. The reflowed bonding material may include a weight fraction of bismuth that is in a range from approximately 4% to approximately 15%. The reflowed bonding material may an alloy that is solid solution strengthened by a presence of bismuth or indium that is dissolved within the reflowed bonding material or a solid solution phase that includes a minor component of bismuth dissolved within a major component of tin. In some embodiments, the reflowed bonding material may include intermetallic compounds formed as precipitates such as Ag3Sn and/or Cu6Sn5.

Dependencies are inferred from the claim text.